java - 如何扩展 c3p0 ComboPooledDataSource

Question

好的，我在 Tomcat 5.5 的 server.xml 中有一个资源，用于数据库连接，如下所示:

<Resource name="jdbc/MyApp" auth="Container" type="com.mchange.v2.c3p0.ComboPooledDataSource" driverClass="com.microsoft.sqlserver.jdbc.SQLServerDriver"  maxPoolSize="100"  minPoolSize="5"   
acquireIncrement="5"    
 user="username" 
password="password"
factory="org.apache.naming.factory.BeanFactory"  
jdbcUrl="jdbc:sqlserver://localhost:1433;databaseName=myDatabase;autoReconnect=true" />

有人试过扩展上面的 ComboPooledDataSource 吗？问题是数据库密码是明文形式。思路是先对密码进行加密，将加密后的 key 放在server.xml中。我有一个解密实用程序，因此我可以在尝试连接到数据库之前解密 key 。

我找到了 org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory 问题的示例解决方案，但我没有使用此连接池。我正在使用 C3P0。以前有人用 C3P0 试过这个吗？

Answer 1

是的，您不能扩展 com.mchange.v2.c3p0.ComboPooledDataSource，因为它是公开的。这是我实现此目的的解决方法。

我扩展了 org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy 并将 com.mchange.v2.c3p0.ComboPooledDataSource 数据源作为构造函数参数传递。

这是我对上述数据源的hibernate.cfg.xml配置:

<bean id="dataSource" class="MyDataSource"> 
        <constructor-arg ref="c3p0DataSource" />
    </bean>

    <bean id="c3p0DataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
        destroy-method="close">
        <property name="driverClass" value="${jdbc.driver.className}" />
        <property name="jdbcUrl" value="${jdbc.url}" />
        <property name="user" value="${jdbc.username}" />
        <property name="password" value="${jdbc.password}" />
        <property name="acquireIncrement" value="${dataSource.acquireIncrement}" />
        <property name="acquireRetryAttempts" value="${dataSource.acquireRetryAttempts}" />
        <property name="acquireRetryDelay" value="${dataSource.acquireRetryDelay}" />
        <property name="autoCommitOnClose" value="${dataSource.autoCommitOnClose}" />
        <property name="breakAfterAcquireFailure" value="${dataSource.breakAfterAcquireFailure}" />
        <property name="checkoutTimeout" value="${dataSource.checkoutTimeout}" />
        <property name="debugUnreturnedConnectionStackTraces"
            value="${dataSource.debugUnreturnedConnectionStackTraces}" />
        <property name="forceIgnoreUnresolvedTransactions"
            value="${dataSource.forceIgnoreUnresolvedTransactions}" />
        <property name="idleConnectionTestPeriod" value="${dataSource.idleConnectionTestPeriod}" />
        <property name="initialPoolSize" value="${dataSource.initialPoolSize}" />
        <property name="maxAdministrativeTaskTime" value="${dataSource.maxAdministrativeTaskTime}" />
        <property name="maxConnectionAge" value="${dataSource.maxConnectionAge}" />
        <property name="maxIdleTime" value="${dataSource.maxIdleTime}" />
        <property name="maxIdleTimeExcessConnections" value="${dataSource.maxIdleTimeExcessConnections}" />
        <property name="maxPoolSize" value="${dataSource.maxPoolSize}" />
        <property name="maxStatements" value="${dataSource.maxStatements}" />
        <property name="maxStatementsPerConnection" value="${dataSource.maxStatementsPerConnection}" />
        <property name="minPoolSize" value="${dataSource.minPoolSize}" />
        <property name="numHelperThreads" value="${dataSource.numHelperThreads}" />
        <property name="propertyCycle" value="${dataSource.propertyCycle}" />
        <property name="testConnectionOnCheckin" value="${dataSource.testConnectionOnCheckin}" />
        <property name="testConnectionOnCheckout" value="${dataSource.testConnectionOnCheckout}" />
        <property name="unreturnedConnectionTimeout" value="${dataSource.unreturnedConnectionTimeout}" />
    </bean>

Mine jdbc.properties file:


jdbc.driver.className=com.microsoft.sqlserver.jdbc.SQLServerDriver
jdbc.url=xxxxx
jdbc.username=xxx
jdbc.password=xxxxxxxxx #Encrytped password here
jdbc.hibernate.dialect=org.hibernate.dialect.SQLServerDialect
hibernate.show_sql=false
hibernate.hbm2ddl.auto=update

dataSource.acquireIncrement=3
dataSource.acquireRetryAttempts=30
dataSource.acquireRetryDelay=60000
dataSource.autoCommitOnClose=false
dataSource.breakAfterAcquireFailure=false
dataSource.checkoutTimeout=0
dataSource.debugUnreturnedConnectionStackTraces=false
dataSource.forceIgnoreUnresolvedTransactions=false
dataSource.idleConnectionTestPeriod=0
dataSource.initialPoolSize=10
dataSource.maxAdministrativeTaskTime=0
dataSource.maxConnectionAge=0
dataSource.maxIdleTime=0
dataSource.maxIdleTimeExcessConnections=0
dataSource.maxPoolSize=10
dataSource.maxStatements=0
dataSource.maxStatementsPerConnection=0
dataSource.minPoolSize=10
dataSource.numHelperThreads=3
dataSource.propertyCycle=0
dataSource.testConnectionOnCheckin=false
dataSource.testConnectionOnCheckout=false
dataSource.unreturnedConnectionTimeout=0


Mine extended class where I decrypt the password before passing the datasource to transaction Proxy wrapper.

import javax.sql.DataSource;

import org.jasypt.util.text.BasicTextEncryptor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy;

import com.csc.emms.common.EMMSConstraints;
import com.mchange.v2.c3p0.ComboPooledDataSource;

public class MyDataSource extends TransactionAwareDataSourceProxy
{
    private static char[] appName =
    {
            'B', 'I', 'N', 'G', 'O', 'D', 'I', 'N', 'G', 'O'
    };

    @Autowired
    // Inject your class by constructor
    MyDataSource(ComboPooledDataSource dataSource)
    {
        super.setTargetDataSource(decryptPassword(dataSource));
    }

    private DataSource decryptPassword(ComboPooledDataSource dataSource)
    {
        dataSource.setPassword(decode(dataSource.getPassword()));
        return dataSource;
    }

    private String decode(String encodedPassword)
    {
        BasicTextEncryptor decoder = new BasicTextEncryptor();
        decoder.setPasswordCharArray(appName);
        return decoder.decrypt(encodedPassword);
    }

    private String encode(String password)
    {
        BasicTextEncryptor encoder = new BasicTextEncryptor();
        encoder.setPasswordCharArray(appName);
        return encoder.encrypt(password);
    }
}
Hope this resolved your issue.